JP2015225888A - Protective cover for electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective cover for an electronic apparatus excellent in transparency without damaging strength, flexibility, water resistance, and heat resistance required for the protective cover for an electronic apparatus.SOLUTION: The protective cover for an electronic apparatus used for covering the electronic apparatus includes a cover body formed by curing a silicon rubber composite. The silicon rubber composite contains phenylvinylmethyl silicon rubber, dry silica, and organic peroxide.

Description

  The present invention relates to a protective cover for an electronic device that is used in an electronic device such as a mobile phone, a smartphone, an electronic dictionary, a digital camera, and a digital audio player, and protects the electronic device.

  In recent years, electronic devices such as mobile phones, smartphones, electronic dictionaries, digital cameras, and digital audio players are frequently used. These electronic devices are often used in a state where the device main body is covered with a protective cover in order to prevent the occurrence of scratches and the like.

  This type of protective cover is required to have high strength, stretchability, water resistance, and heat resistance. Examples of such a protective cover include a silicone rubber composition formed by curing a silicone rubber composition. Are known (see Patent Document 1). Such a protective cover made of silicone rubber is soft, so it is preferred by consumers because it is easy to attach to an electronic device and is familiar to the hand.

JP 2010-190916 A

By the way, recently, there are many consumers who want to use the design and color of the electronic device as it is, and a protective cover made of plastic made of polycarbonate or the like having high transparency is gaining popularity. However, the plastic protective cover is liable to slip off from the hand, and the protective cover itself is easily damaged when dropped. On the other hand, the conventional protective cover made of silicone rubber as described above is advantageous because it is soft and easy to attach to electronic equipment, and is familiar to the hand. It was difficult to ensure the transparency.
For this reason, there is a demand for a protective cover not only excellent in strength, stretchability, water resistance and heat resistance, but also excellent in transparency.

  In view of the above circumstances, the present invention provides an electronic device protective cover excellent in transparency without impairing strength, stretchability, water resistance, and heat resistance required for the protective cover for electronic devices. Let it be an issue.

  In order to solve the above-mentioned problems, the present inventors have intensively researched and found that a cured product obtained by blending a silicone rubber composition with phenylvinylmethylsilicone rubber, dry silica, and an organic peroxide. Has been found to be more transparent than conventional ones. Moreover, by blending phenylvinylmethylsilicone rubber, dry silica, and organic peroxide, the stretchability, water resistance, and heat resistance required as a protective cover for electronic devices are sufficiently maintained. The headline and the present invention were completed.

That is, the protective cover for electrical equipment according to the present invention is:
A protective cover for electronic equipment used to cover electronic equipment,
A cover body formed by curing a silicone rubber composition;
The silicone rubber composition contains phenyl vinyl methyl silicone rubber, dry silica, and an organic peroxide.

  According to such a configuration, the protective cover for electronic equipment is provided by including the cover body formed by curing a silicone resin composition containing phenylvinylmethylsilicone rubber, dry silica, and organic peroxide. In addition, it is excellent in strength, elasticity, water resistance and heat resistance, and relatively excellent in transparency.

In the protective cover for electronic equipment with the above configuration,
The haze value of the cover body is preferably 10% or less.

  Here, the haze value is a maximum value of values measured by the integrating sphere attachment device in the wavelength range of 380 nm to 780 nm, and is a value obtained as a ratio of diffuse transmittance to total light transmittance.

  According to this configuration, when the haze value of the cover main body is 10% or less, the protective cover for electronic devices becomes more excellent in transparency.

In the protective cover for electronic equipment with the above configuration,
It is preferable that the compounding ratio of the phenyl vinyl methyl silicone rubber and the dry silica is 5:95 to 10:90 by mass part.

In the protective cover for electronic equipment with the above configuration,
Further comprising a coating film laminated on the cover body,
The coating film is preferably formed by curing a coating composition containing a condensation curable silicone and a silane coupling agent.

  According to this configuration, by further including the coating film, the protective cover for electronic equipment has excellent slipperiness while maintaining excellent transparency.

  ADVANTAGE OF THE INVENTION According to this invention, the intensity | strength, elasticity, water resistance, and heat resistance which are calculated | required by the protective cover for electronic devices are not impaired, The protective cover for electronic devices excellent in transparency is provided.

It is a perspective view from the front side of the state which mounted | wore the electronic device with the protective cover for electronic devices which concerns on one Embodiment of this invention. Single unit perspective view from the front side of the protective cover for electronic equipment of this embodiment Front view of protective cover for electronic device of this embodiment Rear view of protective cover for electronic device of this embodiment Top view of the protective cover for electronic equipment of this embodiment Right side view and partial enlarged cross-sectional view of the protective cover for electronic equipment of the present embodiment

  Hereinafter, with reference to FIGS. 1 to 6, a protective cover for electronic devices (hereinafter simply referred to as “protective cover”) 1 according to an embodiment of the present invention will be described. In the following description, the electronic device 2 to which the protective cover 1 is attached will be described using a typical smartphone, iPhone (registered trademark of Apple Inc., licensed by Apple).

  First, the electronic device 2 to which the protective cover 1 of this embodiment is attached will be described. As shown in FIG. 1, the electronic device 2 has a substantially rectangular parallelepiped shape with arcuate chamfers formed at four corners and a predetermined thickness (formed flat). The electronic device 2 includes a speaker, a microphone, and the like on the peripheral side surface 3. In addition to the rectangular display screen 4, a home button is provided on the front surface as one surface. The electronic device 2 is provided with a camera lens exposed on the back surface which is the other surface.

Next, the protective cover 1 of this embodiment will be described.
The protective cover 1 according to the present embodiment is a protective cover used to cover the electronic device 2, and includes a cover body 5 formed by curing a silicone rubber composition, and a cover laminated on the cover body 5. And a membrane P. 2 to 5, the protective film 1 is shown without the coating film P.

  Specifically, as shown in FIGS. 2 to 5, the protective cover 1 is a protector that is used to cover the electronic device 2 and mainly has a function of protecting the electronic device 2. The protective cover 1 includes a cover body 5 formed from a silicone rubber composition. The cover body 5 is provided with an opening 5 a so as to expose the display screen 4 of the electronic device 2, and the front wall 6 covering a part of the front surface of the electronic device 2 and the peripheral side portion (side surface) of the electronic device 2. A side wall 7 that covers the entire surface and a back wall 8 that covers the entire back surface of the electronic device 2 are provided. The front wall 6, the side wall 7, and the back wall 8 are integrally formed.

  The front wall 6 can cover the lower front portion of the electronic device 2. A notch 9 a is formed at the center of the front wall 6 in the left-right direction at a position corresponding to the home button of the electronic device 2. In the upper part of the back wall 8, a photographing hole 10 is formed at a site corresponding to the camera lens provided in the electronic device 2.

  The side wall 7 is integrally provided with an edge portion 11 that wraps around the front surface side so as to cover the outer edge of the front surface of the electronic device 2. The edge 11 is formed in a frame shape so as to follow the shape of the outer edge of the front surface of the electronic device 2. In the cover body 5, rectangular openings 12 and 13 that can expose specific portions of the electronic device 2 are formed in at least one of the side wall 7 and the back wall 8.

  Examples of the specific portion include a charging port, a USB port, and the like disposed on the peripheral side of the electronic device 2. In this case, a plurality of these specific portions are arranged side by side on the lower surface of the peripheral side portion. The openings 12 and 13 are respectively formed at portions corresponding to these specific portions. The side wall 7 is formed so as to go around the front edge and the back edge of the electronic device 2. The openings 12 and 13 are formed across the entire width in the front-rear direction of the side wall 7 (the total width in the thickness direction of the electronic device 2).

  An opening 9b is formed at a position corresponding to the power switch of the electronic device 2 on the peripheral side portion of the side wall 7 (upper side in FIG. 3). The opening 9b may be for directly pressing the power switch, or may be for fitting a switch pressing member (not shown) for pressing indirectly. In addition, an opening 9c is formed in the peripheral side portion at a position (left side in FIG. 3) corresponding to a volume control button (not shown) arranged in pairs on the side surface of the electronic device 2. The opening 9c may be for directly pressing the button, or may be for fitting an adjustment pressing member (not shown) for pressing indirectly.

  The cover main body 5 includes opening / closing pieces 14 and 15 that open the openings 12 and 13 by being bent with the edge portions of the openings 12 and 13 as bases. The opening / closing pieces 14 and 15 are formed integrally with other parts, and the openings 12 and 13 are rearwardly closed so as to substantially close the openings 12 and 13 through a gap at the three side edges (front edge and left and right edges) of the openings 12 and 13. With the edge portion as a base, it can be rotated by elasticity due to the silicone rubber composition. A microphone elliptical hole 16 is formed adjacent to the openings 12 and 13.

  The silicone rubber composition contains phenyl vinyl methyl silicone rubber (PVMQ), dry silica, and an organic peroxide.

The phenyl vinyl methyl silicone rubber has a dimethylsiloxane structure having a phenyl group and a vinyl group as side chains. Such phenyl vinyl methyl silicone rubber is in a millable shape and is of a heat curing (vulcanization) type. Moreover, phenyl vinyl methyl silicone rubber is mix | blended with a silicone rubber composition as a base polymer. Moreover, the content rate of the phenyl group in this phenyl vinyl methyl silicone rubber can be made into 10 mol% or less exceeding 0 mol%, for example.
By blending such phenyl vinyl methyl silicone, the protective cover 5 becomes more excellent in transparency than when blending vinyl methyl silicone rubber having no phenyl group.
As such a phenyl vinyl methyl silicone rubber, a commercially available product can be used.

The dry silica is blended as a reinforcing filler. Such dry silica is silica obtained by a gas phase reaction and is also called fumed silica.
By blending such dry silica, the cover body 5 is more excellent in transparency than when wet silica is blended.
As such dry silica, a commercially available product can be used.

The compounding ratio of the phenyl vinyl methyl silicone rubber and the dry silica is not particularly limited and can be set as appropriate. For example, as the dry silica content increases, the strength of the cover body 5 increases, while the stretchability tends to decrease, making it difficult to attach and detach the electronic device 2. Therefore, for example, considering such a viewpoint, it is preferable that, for example, phenylvinylmethylsilicone rubber: dry silica is 5:95 to 10:90 by mass, and the cover body 5 has higher strength. In view of the point, it is more preferable that the mass is 60:40 to 80:20.
The phenyl vinyl methyl silicone rubber and the dry silica may be blended as a premixed mixture.
As such a mixture, for example, a commercially available product can be used. As the commercially available product, phenylvinylmethylsilicone rubber and dry silica are contained in a mixing ratio of 70 parts by mass: 30 parts by mass, and Examples thereof include KE-167-U (manufactured by Shin-Etsu Chemical Co., Ltd.) containing trace components.

The organic peroxide is blended as a curing agent and crosslinks the phenyl vinyl methyl silicone rubber. As such an organic peroxide, a conventionally known one can be used, for example, 2,5 dimethyl-2,5 bis (tertiary butyl peroxy) hexane can be used.
In addition, the organic peroxide may be blended as a mixture of the organic peroxide and silicone rubber in consideration of ease of handling. In this case, it is preferable that 12.5-80 mass% of organic peroxides are contained with respect to the whole mixture, and it is more preferable that 25-80 mass% is contained. Moreover, as a silicone rubber, a commercially available thing can be used. Of the silicone rubbers, phenyl vinylmethyl silicone rubber as described above is preferable.
As a mixture mix | blended as such a hardening | curing agent, a commercial item can be used, for example, As this commercial item, 2,5 dimethyl-2,5-bis (tertiary butyl peroxy) hexane is about 12. C-15 containing 5% by mass, C-8 containing about 25% by mass, C-8A containing about 80% by mass, C-8B containing about 40% (all manufactured by Shin-Etsu Chemical Co., Ltd.) Can be mentioned. In these, the remaining components are phenyl vinyl methyl silicone rubber and a minor component. Of these, C-8A is preferred.

Moreover, it is preferable that the compounding quantity of the organic peroxide with respect to the whole said silicone rubber composition is 0.3 mass%-0.5 mass%, for example.
When the blending ratio is in the above range, there is an advantage that vulcanization is promoted and strength is further increased.

  In addition to phenyl vinyl methyl silicone rubber, dry silica, and organic peroxide, additives that are blended with conventionally known silicone rubber compositions may be blended with the silicone rubber composition as appropriate. As such an additive, for example, a colorant blended for coloring the cover main body 5 for a lineup accompanying sales can be cited.

The cover body 5 formed from the silicone rubber composition as described above preferably has a haze value of 10% or less, more preferably 8% or less, and even more preferably 4% or less.
When the haze value of the cover body 5 is 10% or less, the haze value of the protective cover 1 can be easily reduced to 10% or less, and the protective cover 1 becomes more excellent in transparency.
The haze value is a value measured by an integrating sphere attachment device in the wavelength range of 380 nm to 780 nm, and is a value obtained as a ratio of diffuse transmittance to total light transmittance.

In addition, in order to protect the electronic device 2, the hardness of the cover body 5 is measured by, for example, an Asker rubber hardness meter (C2L type, manufactured by Asker) in terms of excellent strength, elasticity, water resistance, and heat resistance. Sometimes, it is preferably 50 to 60 °.
As for other characteristic values of the cover body 5, the tensile strength is preferably 10.0 to 14.0 MPa, more preferably 12.0 to 13.0 MPa, and the elongation is preferably 400 to 600. %, More preferably 500 to 600%, tear strength is preferably 2.0 to 5.0 MPa, more preferably 3.0 to 4.0 MPa, and impact resilience is preferably 30 to 60%. More preferably, it is 40 to 50%, and the actual hardness is preferably 40 to 70 °, more preferably 50 to 60 °.
Furthermore, since the cover 5 of the present embodiment is excellent in strength as described above, the impact, cracking, and the like when dropped from various actual devices such as a mobile phone, a smartphone, an electronic dictionary, a digital camera, a digital audio player, and a tablet. Scratches can be prevented.

  Further, the thickness of the cover body 5 is preferably set to 0.3 to 0.9 mm for the thickness of the back surface and the front surface, and is set to 0.5 to 0.7 mm in consideration of productivity. It is more preferable. The side wall thickness is preferably set to 1.2 to 1.8 mm. In this embodiment, the thickness of the back and front portions is 0.6 mm, and the thickness of the side portions is 1.5 mm.

The cover body 5 can be manufactured as follows, for example.
That is, among the silicone composition, the phenyl vinyl methyl silicone rubber and the dry silica are put into a kneader, and further an organic peroxide is added, and the mixture is mixed in an environment of 20 to 30 ° C. obtain. Subsequently, the obtained mixture is extended into a plate shape to obtain a plate-shaped molded product. The obtained plate-like molded product is cut to produce a cut piece, and the obtained cut piece is put into a mold and compression-molded while being heated at 170 to 180 ° C. to cure the silicone rubber composition. Thus, the cover body can be produced. Note that deburring or the like may be performed as necessary.

As shown in FIG. 6, the protective cover 1 of this embodiment further includes a coating film P laminated on the cover body 5. In the present embodiment, the coating film P is laminated on the surface of the cover body 5. In this case, the surface of the cover body 5 is a surface that does not come into contact with the electronic device 2. In the present embodiment, as described above, the cover body 5 includes the front wall 6 that covers a part of the front surface of the electronic device 2 so as to expose the display screen 4 of the electronic device 2, and the peripheral side portion (side surface) of the electronic device 2. ) And a back wall 8 that covers the entire back surface of the electronic device 2. That is, the surface of the cover body 5 is a front surface of the front wall 6, the side wall 7, and the back wall 8 that is the opposite side of the surface on the electronic device 2 side.
In the present embodiment, the coating film P is not coated (formed) on the peripheral wall surface of the photographing hole 10, the peripheral wall surfaces of the openings 12 and 13, and the peripheral wall surface of the microphone elliptical hole 16.
Note that the coating film P may be formed on a part of the surface of the cover body 5 or may be formed on the surface of the cover body 5, for example, and the coating part is not particularly limited. .

  The coating film P is formed by curing a coating composition containing a condensation curable silicone and a silane coupling agent.

  Examples of the condensation curable silicone include room temperature curable (vulcanized) silicone (RTV silicone) that cures at room temperature, and examples of the room temperature curable silicone include rubber-based and resin-based room temperature curable silicone, that is, room temperature curable silicone. Examples thereof include rubber and room temperature curable silicone resin.

The silane coupling agent is blended in order to improve the adhesion between the coating film P and the cover body 5.
Examples of the silane coupling agent include conventionally known silane coupling agents such as vinyl silane coupling agents such as vinyltrimethoxysilane and vinyltriethoxysilane; 2- (3,4-epoxycyclohexyl) ethyltrimethoxy. Epoxy silane coupling agents such as silane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane Styryl silane coupling agent such as p-styryltrimethoxysilane; methacrylic silane coupling agent such as 3-methacryloxypropylmethyldimethoxysilane; 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyl Methacrylic silane coupling agents such as tildiethoxysilane and 3-methacryloxypropyltriethoxysilane; Acrylic silane coupling agents such as 3-acryloxypropyltrimethoxysilane; N-2- (aminoethyl) -3- Aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1, Amino-based silane couplings such as 3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride Agent; Tris- (Trimethoxysilyl Ropyl) isocyanurate silane coupling agents such as isocyanurate; ureido silane coupling agents such as 3-ureidopropyltriethoxysilane; mercapto silanes such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane Coupling agents; sulfide-based silane coupling agents such as bis (triethoxysilylpropyl) tetrasulfide; and isocyanate-based silane coupling agents such as 3-isocyanatopropyltriethoxysilane.

  The compounding ratio of the condensation curable silicone and the silane coupling agent is not particularly limited.

The condensation curable silicone and the silane coupling agent may be used as a mixed solution prepared by dissolving in a solvent.
As the solvent, for example, toluene, heptane or the like is used, and these may be used as a mixed solution.
In this case, the condensation curable silicone and the silane coupling agent can be blended so that the nonvolatile content in the mixed solution is preferably 5 to 30% by mass, more preferably 10 to 25% by mass.
As such a mixed solution, for example, a commercially available product can be used, and as the commercially available product, for example, it is commercially available as a surface slipperiness-imparting coating agent, and has a room temperature curable silicone resin as a condensation curable silicone. X-93-1710 (non-volatile content: 24% by mass), X-93-1755-1 (non-volatile content: 12% by mass), X-93-1755-2 (non-volatile content: 11% by mass) having a room temperature curable silicone rubber ( All of them are manufactured by Shin-Etsu Chemical Co., Ltd.).

  In addition to the above, other additives may be blended in the coating composition.

  Although the thickness of the said coating film P is not specifically limited, For example, it can set to 10-20 micrometers.

The coating film P can be manufactured, for example, as follows.
That is, the liquid mixture containing the condensation curable silicone, the silane coupling agent, and the solvent is applied to the cover body 5 using an application device and dried. Thereby, the solvent is dried, the coating composition containing the condensation-curable silicone and the silane coupling agent is cured, and the coating film P is formed. In addition, you may heat after application | coating as needed.
The cover main body 5 is a surface that comes into contact with the electronic device 2 by attaching the cover main body 5 to a jig (not shown) having the same shape as the outer shape of the electronic device 2 and applying the mixed liquid to the cover. It is possible to prevent the coating film P from being formed on the back surface of 5.

The haze value of the protective cover 1 is preferably 10% or less, more preferably 8% or less, and further preferably 4% or less.
When the haze value of the protective cover 1 is 10% or less, the protective cover 1 becomes more excellent in transparency.

In addition, the hardness of the protective cover 1 is measured by, for example, an Asker rubber hardness meter (C2L type, manufactured by Asker) in terms of excellent strength, elasticity, water resistance, and heat resistance to protect the electronic device 2. Sometimes, it is preferably 50 to 60 °.
As for other characteristic values of the protective cover 1, the tensile strength is preferably 10.0 to 14.0 MPa, more preferably 12.0 to 13.0 MPa, and the elongation is preferably 400 to 600. %, More preferably 500 to 600%, tear strength is preferably 2.0 to 5.0 MPa, more preferably 3.0 to 4.0 MPa, and impact resilience is preferably 30 to 60%. More preferably, it is 40 to 50%, and the actual hardness is preferably 40 to 70 °, more preferably 50 to 60 °.
Furthermore, since the protective cover 1 of this embodiment is excellent in strength as described above, the impact, cracking, and the like at the time of dropping from various real machines such as a mobile phone, a smartphone, an electronic dictionary, a digital camera, a digital audio player, and a tablet And scratches can be prevented.

  The thickness of the protective cover 1 is preferably set to 0.3 to 0.9 mm for the thickness of the back surface and the front surface, and is set to 0.5 to 0.7 mm in consideration of productivity. It is more preferable. The side wall thickness is preferably set to 1.2 to 1.8 mm. In this embodiment, the thickness of the back and front portions is 0.6 mm, and the thickness of the side portions is 1.5 mm.

  As described above, the protective cover 1 of the present embodiment includes the cover body 5 formed by curing a silicone resin composition containing phenyl vinyl methyl silicone rubber, dry silica, and organic peroxide. Thus, the strength, stretchability, water resistance and heat resistance required for the protective cover for electronic devices are not impaired, and the transparency is excellent.

  In addition, the protective cover 1 of the present embodiment further includes the coating film P laminated on the cover body 5 so that the protective cover 1 has excellent slipperiness while maintaining excellent transparency. It becomes.

Here, since the cover body 5 has the characteristics of silicone rubber, the grip feeling is good, but dust tends to adhere to the electronic device 2 when it is carried or used.
However, by providing the coating film P, in particular, by providing the coating film P laminated on the surface of the cover body 5 that is a surface that does not contact the electronic device 2, it is difficult for dust to adhere. Moreover, it becomes easy to remove the attached dust. For this reason, even if dust adheres to the surface of the protective cover 1 when the electronic device 2 is used or when the electronic device 2 is stored in a bag, for example, dust that is anxious to be wiped by the user is easily removed. The electronic device 2 can be comfortably used.

  Moreover, since the protective cover 1 is rich in flexibility and fits into the shape of the electronic device 2, it is easy to attach to the electronic device 2. In mounting the protective cover 1 on the electronic device 2, specifically, for example, the elasticity of the cover body 5 is used (by extending the cover body 5), and the electronic device 2 is attached to the cover body 5 from the opening 5a. And the back wall 8 of the cover body 5 covers the back surface of the electronic device 2, the side wall 7 of the cover body 5 covers the peripheral side of the electronic device 2, and the front wall of the cover body 5 6 covers a part of the front surface of the electronic device 2. By doing in this way, the electronic device 2 can be protected from scratches or the like.

  Moreover, the protective cover 1 of this embodiment is not limited to the cover that covers the above-described smartphone as the electronic device 2, but also covers a part of a mobile phone, a tablet PC, an electronic dictionary, a digital camera, and a digital audio player. Alternatively, the present invention can also be applied as a cover that covers a part of an earphone such as a keyboard, a mouse, or the like that is a PC peripheral device. Among these, it is particularly suitable for smartphones and tablet PCs.

  The protective cover for an electronic device according to the present embodiment is as described above, but the present invention is not limited to the above-described embodiment, and can be appropriately changed in design within the intended scope of the present invention.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to these.

Example 1
As a mixture of the phenyl resin methyl silicone rubber of the silicone resin composition and dry silica, a commercially available KE167U (manufactured by Shin-Etsu Chemical Co., Ltd.) and a commercial product C-8A (manufactured by Shin-Etsu Chemical Co., Ltd.) as an organic peroxide, Was used. After these were mixed in a temperature environment of 20 to 30 ° C., the obtained mixture was molded into a plate shape by OSS A3 type 600 (manufactured by Sugano Seiki Seisakusho). The obtained plate-like molded product is cut, and the cut piece is put into a mold of a compression molding machine (trade name KRP-100-4, manufactured by Yao Machinery Co., Ltd.) and compression molded at 170 to 180 °. The cover main body 5 having the shape described in FIGS. 2 to 5 was obtained. The thickness of the back and front portions of the cover body was set to 0.6 mm, and the thickness of the side portions was set to 1.5 mm.
The surface of the obtained cover body (on the side opposite to the electronic device) was applied using a commercially available X-93-1755-1 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a mixed liquid of the coating composition and a solvent, It was made to dry and the coating film was formed, and the laminated body was obtained. In this way, a protective cover was produced.
Integrating sphere attachment device (integrated sphere ISV-469 attached to UV-visible spectrophotometer V-560 in the wavelength range of 380 to 780 nm through the light from the back side to the front side of the back portion of the protective cover obtained ( The haze value measured by JASCO Corporation was 3%.
Further, when the transmittance was measured by an ultraviolet-visible spectrophotometer V-560 (manufactured by JASCO Corporation), it was 82% at 400 nm, 87% at 550 nm, and 89% at 700 nm.
Further, when the tensile strength of the back surface portion was measured according to JIS K 6249-1983 “Testing method for uncured and cured silicone rubber”, it was 12.2 MPa, and the elongation at that time was 550%. there were. The tear strength of the back surface portion was measured according to JIS K 6249-1983 "Vulcanized rubber and thermoplastic rubber-Determination of tensile properties" and found to be 3.4 MPa. In accordance with ISO4662-1986 "vulcanized rubber or thermoplastic rubber-how to obtain rebound resilience", the drop height (mm) and the rebound height (mm) are measured, and the rebound height / drop height x 100 Based on the calculation formula, the impact resilience of the back surface portion was calculated to be 46%. When the actual hardness was measured with an Asker hardness meter (C2L type, manufactured by Asker), it was 53 °.

(Comparative Example 1)
In place of phenyl vinyl methyl silicone rubber, a protective silicone cover is used in the same manner as in Example 1 except that vinyl silicone rubber having no phenyl group (dimethyl vinyl silicone rubber) is used and wet silica is used instead of dry silica. Produced.
About the obtained cover main body, when it carried out similarly to Example 1 and measured the haze value, it was 90.6%.
Further, the transmittance was measured in the same manner as in Example 1. As a result, it was 2% at 400 nm, 3% at 550 nm, and 4% at 700 nm.
Other characteristic values were comparable to those of the protective cover of Example 1.

DESCRIPTION OF SYMBOLS 1 ... Protective cover, 2 ... Electronic device, 3 ... Circumferential side surface, 4 ... Display screen, 5 ... Cover main body, 5a ... Opening, 6 ... Front wall, 7 ... Side wall, 8 ... Back wall, 9a, 9b, 9c ... Opening DESCRIPTION OF SYMBOLS 10 ... Hole for imaging | photography, 11 ... Edge part, 12, 13 ... Opening, 14, 15 ... Opening-closing piece, 16 ... Elliptical hole, P ... Covering film

Claims (4)

A protective cover for electronic equipment used to cover electronic equipment,
A cover body formed by curing a silicone rubber composition;
The silicone rubber composition is a protective cover for electronic equipment containing phenyl vinyl methyl silicone rubber, dry silica, and an organic peroxide.   The protective cover for electronic devices according to claim 1, wherein the haze value is 10% or less.   The protective cover for an electronic device according to claim 1 or 2, wherein a blending ratio of the phenyl vinyl methyl silicone rubber and the dry silica is 5:95 to 10:90 by mass part. Further comprising a coating film laminated on the cover body,
The protective cover for electronic devices according to any one of claims 1 to 3, wherein the coating film is formed by curing a coating composition containing a condensation curable silicone and a silane coupling agent.